Can Voting Be Rational When One Vote Rarely Decides?

In an election with many participants, the chance that one ballot will happen to change the winner is usually very small. If the sole purpose of voting is for “my vote” to produce my preferred result directly, the cost in time may exceed its expected benefit. This generates the so-called paradox of voting. Yet the inference quietly fixes the aim of the action: it treats voting only as an individual instrument for controlling the outcome.

Political philosophy offers no single answer. Some theories understand voting as an expression of commitment. Others emphasise sharing in the production of a public decision, bearing part of the responsibility for sustaining democratic institutions, or avoiding leaving all participation costs to others. On these accounts, a ballot may belong to a joint action even when it is not decisive. Still, “it would be disastrous if nobody voted” does not by itself prove that everybody has a duty to vote. The same form of argument would absurdly imply that everyone must become a farmer because a world without farmers would starve.

My view is that “one vote makes no difference” defeats an inflated causal picture, not voting itself. Whether voting is rational depends on whether a person values changing the result, participating in a common decision, or discharging a civic responsibility. Those reasons must still be compared with the cost of becoming informed and with other forms of public action. A vote is neither a magic button nor mere statistical noise; it is a practice whose purpose must be made explicit.

https://plato.stanford.edu/entries/voting/